Dental instrument



Aug. 15, 1950 A. E. HAAS DENTAL INSTRUMENT Fi led Sept. 7, 1948 Alfred E. I Haas INVENTOR.

BY 2 ml Patented Aug. 15, 1950 r L UNITE-D DFFIICE Y i This invention relates tojimprovernents in dental instruments and has for'its primary object theprovision of a retainer for use with silicate, cement or other plastic fillings in any of the anterior teeth, upper or lower.

Another object of the invention is to provide a novel dental clamp for retaining the conventional plastic strip or matrix about a filling or fillings set in the anterior teeth. In filling certain teeth, particularly the anteriors, with plastic fillings, flexible Celluloid or other suitable bands or matrices are employed to keep fillings in place in the cavities until the fillings have set. The instant invention is directed to a clamp for this purpose so constructed that it will effectively fit in place and produce desired results without interfering with the dentist or annoying the patient.

Another object of the invention is to provide a dental clamp of the class described which is simple, strong, durable, inexpensive and well adapted to the purpose for which it is designed.

These, together with various ancillary objects and features of the invention which will later become apparent as the following description proceeds, are attained by the device, a preferred embodiment of which has been illustrated by way of example only in the accompanying drawings, wherein:

Figure 1 is a top plan view of the device in use on upper anterior teeth;

Figure 2 is a top plan view of the device per so when not in use; I

Figure 3 is a side elevational view of the device;

Figure 4 is a rear elevational view of the device;

7 Figure 5 is a longitudinal sectional view through the device; and

Figure 6 is an end elevational view taken from the plane of line 66 and looking in the direction of the arrows.

Specific reference is now made to the drawings. In the several views in the accompanying drawings and in the following specification similar reference characters indicate corresponding elements throughout.

Indicated at ID is a front lever arm having a pointed spur l2 at one end for introduction into the interproximal space above and below the contact point of the anterior teeth and a fiat handle portion Id at the other end thereof. A second or back lever arm l6 having a similar spur l8 at one end and a fiat handle portion at the other is pivoted by means of a pivot pin 22 to the front lever arm intermediate the ends of both arms. Each of the arms are further provided withapai'r of lateral flanges 24 forming a U shaped channel in each arm for receiving the end portions 26 of a coil spring 28 which'is wound about the pivot pin as at 30. This spring normally urges the opposed spurs I2 and [8 towards each other in a closed position.

The back arm I6 is further provided at the spur end with a laterally extending plate 32 upon which is secured, by means of cement or other suitable material and on both sides of the spur l8, pliable material 34, such as rubber, plastic, cotton or wood fiber which will conform to the back of the teeth and adapt the rear portion 36 of the matrix. as shown in Figure 6.

To adapt the front portion 38 of the matrix to the teeth, a special means is provided which is indicated at 4B and consists of the following essential elements. A bifurcated member 42 having a web portion 44 and furcations or arms 46 and 48 is pivoted as at 50 adjacent its web portion to the back lever arm 16. To each of the furcations 45 and 48 are secured as at 52 a preferably arcuated resilient finger 54. Thus two fingers are provided which straddle the front lever arm in at the spur end thereof.

To urge the fingers 54 against the front matrix portion 38, a relatively strong and flat leaf spring 56 is secured as at 58 to the outer f ce of the plate 32 and abuts the outer edge of the web portion 44, as shown in Figures 3 and 5. For proper manipulation, the dentist often desires that the front matrix portion 38 be free or unclamped, in which case he would want the finger 54 to be retained in a fixed open position. To accomplish this, the web portion 44 is provided additionally with an arcuated surface 60 and when the fingers are moved back to assume the position shown in dotted lines in Figure 3, the leaf spring 56 will abut the arcuated surface 60 and automatically retain the fingers in an open position as shown.

In view of the foregoing description taken in conjunction with the accompanying drawings it is believed that a clear understanding of the device will be quite apparent to those skilled in this art. A more detailed description is accordingly deemed unnecessary.

It is to be understood, however, that even though there is herein shown and described a preferred embodiment of the invention the same is susceptible to certain changes fully comprehended by the spirit of the invention as herein described and the scope of the appended claims.

Having described the invention, what is claimed as new is:

1. A dental instrument for use in filling anterior teeth comprising a back lever arm and a front lever arm pivotally interconnected intermediate their ends, handle portions at the lower ends of said arms, opposed spurs at the upper ends of said arms, resilient means between said arms normally urging said spurs towards each other, a transversely extending plate secured to the upper end of said back lever behind said spur, means carried by said back arm for retaining a matrix upon the teeth about a filling, said lastnamed means including pliable material carried by said plate at both sides of said spur for retaining a portion of the matrix against the back of the teeth, and a pair of resilient fingers for retaining a portion of the matrix against the front of the teeth, and means for pivotingsaid fingers to said back lever arm. H w

2. The combination of claim 1 wherein said means for pivoting said fingers includes a bifurcated member pivoted adjacent its web portion to said back lever arm, said fingers being secured to the free ends of the furcations of the bifurcated member.

3. The combination of claim 2 and means for selectively retaining said fingers in an open and closed position upon said back lever arm.

4. The combination of claim 3 wherein said means for selectively retaining said fingers includes a leaf spring secured to the rear of said plate, the free end of which abuts the web portion of said bifurcated member.

5. The combination of claim 4 wherein said web portion of said bifurcated member has an arcuated surface permitting said leaf spring to retain said fingers in an open position.

ALFRED E. HAAS.

REFERENCES CITED J The following references are of record in the file of this patent:

UNITED STATES PATENTS Parkin Dec. 30, 1941 

